All the keyboard shortcuts you can use when starting up your MacYou can boot your Mac in different modes or reset different parameters with keyboard shortcuts.
Sometimes your Mac isn't running properly, so you need to reset the NVRAM and PRAM. Sometimes you need to boot in Recovery Mode in order to reinstall an OS or recover your hard drive via the internet. Whatever your needs, you can boot your Mac in a variety of modes in order to complete a task before startup; all you need to do is press some keys down and wait for the chime (unless you have a later MacBook Pro, in which case I'm sorry).
Here are all the keyboard shortcuts you can use when starting up your Mac!
Start up in safe mode
Startup Manager
Start up from an available external disk
Start up from Apple Hardware Test or Apple Diagnostics
Start up from a NetBoot server
Reset the NVRAM and PRAM
Start up in Recovery Mode
Start up in single-user mode
Start up in target disk mode
Start up from the macOS startup disk when other disks are available
Start up in verbose mode
Eject removable m...
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All the keyboard shortcuts you can use when starting up your Mac
